Hattie Morahan is mystified by the fact she was cast as a parish school teacher in a new Second World War drama My Mother And Other Strangers, as a result of her role in Outnumbered.

“I pop up as this really awful character Jane,” says the 38-year-old. “I mean a lovely character but the most annoying woman in the world, always has a crisis and completely un-self-aware.”

And yet Barry Devlin wrote the new six-part series with Morahan in mind for the lead role, Rose Coyne. “This has never happened to me before,” reveals the actress whose father is TV and film director Christopher Morahan, and whose mother, Anna Carteret, is also an actress. “They sent the scripts over with an accompanying letter from Barry. He’d seen me as Rose, and that was incredibly flattering.”

Set in a rural parish in Northern Ireland, the series follows the fortunes of the Coyne family and their neighbours, as they struggle to maintain a normal life after a United States Army Air Force sets up camp close by. “There are thousands of people being plonked in a farm community like a spaceship, and [the story looks at] what tensions that throws up and how one reacts to them,” explains Morahan.

“And then also the tensions in Northern Ireland, and my character being English and being an outsider.”

My Mother And Other Strangers, BBC1, Sunday, 9pm.

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